Grimoire and the Cauldron (bevy_grimoire)
The grimoire is the book of spells a game loads (bevy_grimoire and bevy_grimoire_core). The Cauldron is the coven’s editor, where you write it: a world editor for Bevy games where you build levels with an AI agent, the Familiar, working beside you. The Familiar changes a map only through the same named operations you use, its changes join your one undo history, and you show it what you mean by snipping a rectangle of the editor with a note.
The demo
64 seconds on a walled map: the agent frames two wall pieces, turns wall_02_2 to 90 degrees and removes wall_02_3; the person’s Cmd+Z reports put back wall_02_3. It ends with a snip: the person drags a box over the walled cluster, writes a note, and the receipt names the PNG it saved.
Add it
The editor is a program you run from a clone, on your game’s project:
git clone https://github.com/bevy-coven/bevy_grimoire
cd bevy_grimoire
cargo run -p bevy_cauldron -- /path/to/your/game
Your game links only the libraries: cargo add bevy_grimoire_core bevy_grimoire. bevy_grimoire_core is engine-free and holds the grammar and the solvers; bevy_grimoire puts a library and a map into a Bevy world (GrimoirePlugin), and GrimoireLivePlugin reloads them while the game runs, so an edit shows up about a second later. A project from before the rename keeps its data in assets/emerge; the editor moves it to assets/grimoire the first time it opens the project.
What it gives you
- Maps built from kits: place, fill, turn, remove and undo (building maps).
- Layouts learned from a corner you laid out and continued with wave function collapse, drawn before you keep them.
- Kits and labels, with a vision model’s proposals marked unchecked until you confirm them (kits and labels).
- The MCP server,
bevy_cauldron_mcp, whose tools (grimoire_state,grimoire_apply_operation, captures, snips) let the Familiar read and drive the open editor (MCP tools). - Panels for the rest of the coven, each editing that crate’s own settings (using a crate in the Cauldron).
Use it in the Cauldron
This is the Cauldron. Every other crate’s page says what the Cauldron does with it.